According to narrations, there are many rites to be advisably performed at the fifteenth night of Rajab:
First: Bathing is an advisable act at this night.
Second: As said by ‘Allamah al-Majlisi, It is recommended to spend this whole night with acts of worship.
Third: It is recommended to visit the holy shrine of Imam al-Husayn (a.s.) at this night.
Fourth: It is also recommended to offer the six-unit prayer previously mentioned within the rites of the thirteenth night.
Fifth: It is recommended to offer a prayer consisting of thirty units in each of which one should recite Surah al-Faatehah one time and Surah al-Tawheed ten times. Sayyid Ibn Tawus has reported this prayer from the Holy Prophet (s.a.w.a.) with an abundant reward.
It is recommended to offer another prayer consisting of twelve units in each of which Surahs of al-Faatehah, al-Tawheed, al-Falaq, al-Nas, al-Qadr, and Ayah al-Kursi should be recited four times EACH. After accomplishing the prayer, one should repeat the following litany four times:
اللّٰهُ اللّٰهُ رَبِّیْ لَا اُشْرِکُ بِہِ شَیْئًا وَلَا اتَّخِذُ مِنْ دُونِہٖ وَلِیًّا
Allah, Allah is my Lord. I do not associate anyone with Him and I do not betake any Master other than Him.
You may then submit his requests.